Adjustable-pivot pliers

ABSTRACT

A pair of pliers, having angled jaws, in which the two plier members are pivoted together by a screw adjustable pivot. One plier member is pivoted by a pivot pin fixed to a block defining an interiorly threaded passageway normal to said pivot pin. A bolt, rotatably mounted by upper and lower end bearings in a slot defined in the other plier member, is threaded complementary to said threaded passageway. The plier members are joined by the engagement of the threaded bolt in the threaded passageway. The upper end bearing is sized for rotation of the upper end of the bolt therein. The lower end bearing is smaller in diameter than the threaded intermediate section of the bolt and extends slightly beyond the lower end of said lower end bearing. A threaded extension of the lower end of the bolt engages a retaining knurled thumb nut to hold the bolt supported in its upper and lower end bearings without binding and with only slight axial movement. The pivot pin of the block is made slightly longer than the thickness of said one plier member at the pivot. A threaded extension of the pivot pin engages a retaining nut to hold said one member on the pivot pin without binding and with only slight axial movement. Said one member is recessed at the area of pivoting and the angled jaw of said other member is transversely displaced to bring, in combination, the respective angled jaws in opposition.

United States Patent [1 1 Burthardt 1 Oct. 30, 1973 1 ADJUSTABLE-PIVOT PLIERS [76] Inventor: Charles J. Burthardt, 1800 Elizabeth Ave., Metairie, La. 70003 22 Filed: Oct. 21, 1971 211 Appl. No.: 191,309

Related US. Application Data [63] Continuation-impart of Ser. No. 878,030, Nov. 19,

1969, abandoned.

Primary Examiner1-larold D. Whitehead Assistant Examiner-Roscoe V. Parker Attorney-James B. Lake, Jr.

[57] ABSTRACT A pair of pliers, having angled jaws, in which the two plier membersare pivoted together by a screw adjustable pivot. One plier member is pivoted by a pivot pin fixed to a block defining an interiorly threaded passageway normal to said pivot pin. A bolt, rotatably mounted by upper and lower end bearings in a slot defined in the other plier member, is threaded complementary to'said threaded passageway. The plier members are joined by the engagement of the threaded bolt in the threaded passageway. The upper end bearing is sized for rotation of the upper end of the bolt therein. The lower end bearing is smaller in diameter than the threaded intermediate section of the bolt and extends slightly beyond the lower end of said lower end bearing. A threaded extension of the lower end of the bolt engages a retaining knurled thumb nut to hold the bolt supported in its upper and lower end bearings without binding and with only slight axial movement. The pivot pin of the block is made slightly longer than the thickness of said one plier member at the pivot. A

V threaded extension of the pivot pin engages a retaining jaws in opposition.

1 Claim, 5 Drawing Figures 7 PAIENTEBnmao ms FIG,

FIG. 5

//v VENTOP CHARLES a. BUPTHARDT ADJUSTABLE-PIVOT PLIERS This application for patent is a continuation-in-part of my patent application for Adjustable Pliers filed 19 Nov. 1969, Ser. No. 878,030 and now abandoned.

The invention relates generally to plaiers and more particularly to pliers with angled jaws and in which the jaws can be adjusted to open and close without a corre sponding movement of the plier handles.

An object of the invention is to provide a pair of angled jawed pliers in which the jaws can be screw adjusted to set an initial opening of the jaws which are then controllable by the handles.

Another object of the invention is to reduce the number of parts and binding effects therebetween in adjustable pliers.

Still another object is to reduce the size and mass of an adjustable pair of pliers by a combination of partially recessing a plier member and transversely offsetting the jaw of the other plier member to effect full opposition of the jaws.

Other objects and a fuller understanding of the invention msy be had by referring to the following specifications, claims and drawings, in which:

FIG. I is a side view of the invention,

FIG. 2 is a sectional view taken along section lines 2--2 of FIG. 1,

FIG. 3 is a sectional view taken along section lines 33 of FIG. 1,

FIG. 4 is a three dimensional view of an adjustable pivot assembly of the invention, and,

FIG. 5 is a plan view of the transversely offset jaw.

Referring to the drawings, the invention comprises two plier members 1 and 2 respectively, adjustably pivoted together by means of a partially threaded bolt 3 rotatably engaging in a complementary threaded block 4 on which a pivot pin 4a is fixed normal to engaged bolt 3. Plier member 2 defines a hole for rotatably mounting it on pivot pin 4a and securing it thereon by a nut 5 engaging a threaded pivot pin extension 4b. Plier member 2 is joined to plier member 1 by inserting block 4 into a slot 1a defined in member 1, and introducing partially threaded bolt 3 into the slot 1a through an upper bearing opening 1b to rotatably engage block 4 by means of relative rotation of their complementary screw threads. The bolt 3 extends into slot 1a until the base of screw threads 3a abutts the base of the slot 1a. Upper and lower unthreaded extensions 3b and 30 respectively of bolt 3 are rotatably engaged in upper and lower bearings 1d and 1e defined in member 1 and positioned in axial continuation of slot 1a. The bolt 3 is retained is retained in the slot In by a knurled retaining thumb nut 6 engaging a threaded extension 3d of bolt 3. Rotation of bolt 3 by means of the thumb nut 6 causes the block 4 and pivot pin 4a fixed thereon to travel up and down the length of slot 1a to open and close the jaws If and 2a of said plier members 1 and 2 to initial openings without moving the handles 1g and 2b respectively.

In amplification of the above brief description, the slot la is made wide enough to allow the passage of block 4 up and down therein without touching the sides thereof (see FIG. 1). The pivot pin 4a is longer than the recessed area 2c is thick to project 0.001 inch therebeyond in order that the retaining; nut 5 binds thereon rather than on plier member 2 (see FIG. 3). Similarly lower unthreaded extension 30 of bolt 3 extends 0.001 inch beyond lower bearing' 1e so that the knurled thumb nut 6 binds thereon to rotate bolt 3 therewith without binding bolt 3 against abutting base 1c (see FIG. 2)

The jaws If and 2a of members 1 and 2 respectively would be offset by the thickness of recess area 2c of member 2 (see FIG. 3). However jaw If is offset this amount (see FIG. 5) to bring the jaws into full opposition.

The complementary male and female threads of bolt 3 and block 4 are preferably of the acme type having a pitch of approximately half the diameter.

What is claimed is:

1. Screw type adjustable-pivot pliers having a pair of plier members extending generally longitudinally with parallely angled jaws, said plier members being pivoted together adjacent said jaws on a transverse axis that is relatively adjustable normal thereto, said pliers comprising: a first plier member defining a rectangular slot with opposed parallel sides and opposed parallel ends normal to said sides, and defining upper and lower cylindrical bearings congruent, aligned and in a plane with said rectangular slot, and said first plier member having its angled jaw transversely offset from said plane of said rectangular slot; a bolt journaled on oppositely disposed ends and threaded intermediate said ends rotatively mounted in said rectangular slot solely by said journaled oppositely disposed ends engaging respectively in said upper and lower cylindri-cal bearings; a tapped block having female threads complementary to threads of said bolt and cooperatively engaged therewith for traveling in said slot between the journaled ends of said bolt when it is rotated; a pivot-pin fixed to said block by an end and normal to said female threads, said pivot-pin defining a journal; a second plier member defining a transverse slot and bearing adjacent its angled jaw for engaging the journal defined by said pivot-pin and, in combination, to pivotally join said first plier member to said second plier member in said transverse'slot and thereby bringing said parallely angled jaws into full opposition without double slotting either of said plier members; and securing means associated respectively with said journals for retaining them in their respective bearings. 

1. Screw type adjustable-pivot pliers having a pair of plier members extending generally longitudinally with parallely angled jaws, said plier members being pivoted together adjacent said jaws on a transverse axis that is relatively adjustable normal thereto, said pliers comprising: a first plier member defining a rectangular slot with opposed parallel sides and opposed parallel ends normal to said sides, and defining upper and lower cylindrical bearings congruent, aligned and in a plane with said rectangular slot, and said first plier member having its angled jaw transversely offset from said plane of said rectangular slot; a bolt journaled on oppositely disposed ends and threaded intermediate said ends rotatively mounted in said rectangular slot solely by said journaled oppositely disposed ends engaging respectively in said upper and lower cylindri-cal bearings; a tapped block having female threads complementary to threads of said bolt and cooperatively engaged therewith for traveling in said slot between the journaled ends of said bolt when it is rotated; a pivot-pin fixed to said block by an end and normal to said female threads, said pivot-pin defining a journal; a second plier member defining a transverse slot and bearing adjacent its angled jaw for engaging the journal defined by said pivot-pin and, in combination, to pivotally join said first plier member to said second plier member in said transverse slot and thereby bringing said parallely angled jaws into full opposition without double slotting either of said plier members; and securing means associated respectively with said journals for retaining them in their respective bearings. 